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How do I copy to the clipboard in JavaScript?
...
document.body.appendChild(textArea);
textArea.focus();
textArea.select();
try {
var successful = document.execCommand('copy');
var msg = successful ? 'successful' : 'unsuccessful';
console.log('Fallback: Copying text command was ' + msg);
} catch (err) {
consol...
How do you debug MySQL stored procedures?
...E debug_msg(enabled INTEGER, msg VARCHAR(255))
BEGIN
IF enabled THEN
select concat('** ', msg) AS '** DEBUG:';
END IF;
END $$
CREATE PROCEDURE test_procedure(arg1 INTEGER, arg2 INTEGER)
BEGIN
SET @enabled = TRUE;
call debug_msg(@enabled, 'my first debug message');
call debug_msg(@ena...
How do I get SUM function in MySQL to return '0' if no values are found?
...
Use COALESCE to avoid that outcome.
SELECT COALESCE(SUM(column),0)
FROM table
WHERE ...
To see it in action, please see this sql fiddle: http://www.sqlfiddle.com/#!2/d1542/3/0
More Information:
Given three tables (one with all numbers, one with all nul...
Xcode 4: How do you view the console?
...nces -> Alerts and click on 'Run starts' on the left hand column.
Then select 'Show Debugger' and when you run the app the NSLog output will be displayed below the editor pane.
This way you don't have to select on the 'up arrow' button at the bottom bar.
...
jQuery select all except first
In jQuery how do I use a selector to access all but the first of an element? So in the following code only the second and third element would be accessed. I know I can access them manually but there could be any number of elements so thats not possible. Thanks.
...
Changing navigation bar color in Swift
...UIColor.whiteColor()
UINavigationBar.appearance().barTintColor = Style.SELECTED_COLOR
UINavigationBar.appearance().translucent = false
UINavigationBar.appearance().clipsToBounds = false
UINavigationBar.appearance().backgroundColor = Style.SELECTED_COLOR
UINavigationBar.appearance...
Selecting pandas column by location
...ed in future versions. See pandas.pydata.org/pandas-docs/dev/… on how to select by position using iloc/iat.
– Wouter Overmeire
Apr 12 '13 at 10:04
1
...
What is the relative performance difference of if/else versus switch statement in Java?
... just ints. From the Java Tutorials: "A switch works with the byte, short, char, and int primitive data types. It also works with enumerated types (discussed in Enum Types), the String class, and a few special classes that wrap certain primitive types: Character, Byte, Short, and Integer (discussed ...
Faster way to develop and test print stylesheets (avoid print preview every time)?
...P (Mac) or Ctrl+Shift+P (Windows, Linux))
2. Start typing Rendering and select Show Rendering.
3. For the Emulate CSS Media dropdown, select print.
UPDATE 29/02/2016
The DevTools docs have moved and the above link provides inaccurate information. The updated docs regarding Media type em...
Heroku Postgres - terminate hung query (idle in transaction)
...'s not desirable or not an option ...)
Find the PID by running this sql:
SELECT pid , query, * from pg_stat_activity
WHERE state != 'idle' ORDER BY xact_start;
(The query may need mending dependent of the version of postgres - eventually, just select * from pg_stat_activity). You'll find the ...